title: Experimental study of the bio-oil production from sewage sludge by supercritical conversion process.
abstract: Environment-friendly treatment of sewage sludge has become tremendously important. Conversion of sewage sludge into energy products by environment-friendly conversion process, with its energy recovery and environmental benefits, is being paid significant attention. Direct liquefaction of sewage sludge into bio-oils with supercritical water (SCW) was therefore put forward in this study, as de-water usually requiring intensive energy input is not necessary in this direct liquefaction. Supercritical water may act as a strong solvent and also a reactant, as well as catalyst promoting reaction process. Experiments were carried out in a self designed high-pressure reaction system with varying operating conditions. Through orthogonal experiments, it was found that temperature and residence time dominated on bio-oil yield compared with other operating parameters. Temperature from 350 to 500°C and reaction residence time of 0, 30, 60min were accordingly investigated in details, respectively. Under supercritical conversion, the maximum bio-oil yield could achieve 39.73%, which was performed at 375°C and 0min reaction residence time. Meanwhile, function of supercritical water was concluded. Fuel property analysis showed the potential of bio-oil application as crude fuel.
authors.affiliation: School of Environmental Science and Technology, State Key Laboratory of Engines, Tianjin University, Tianjin 300072, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Guanyi
authors.initials: G
authors.lastname: Chen
authors.forename: Yanbin
authors.initials: Y
authors.lastname: Li
authors.forename: Beibei
authors.initials: B
authors.lastname: Yan
authors.forename: Donghui
authors.initials: D
authors.lastname: Pan
mesh_terms: D056804:Biofuels / Q000032:analysis; D012722:Sewage; D013696:Temperature; D013818:Thermogravimetry
chemical_list: D056804:Biofuels; D012722:Sewage
keywords: Bio-oil; Direct liquefaction; Sewage sludge; Supercritical water